Chert / Flint
Chert (Cryptocrystalline Silica, SiO2)
sedimentary
Category
Man Made Glass (Not A Natural Rock Or Mineral)
Browse man made glass (not a natural rock or mineral) specimens identified by the Rock Identifier community.
Chert (Jasper)
Microcrystalline Quartz (SiO2) with iron oxide impurities
sedimentary
Chert Breccia
Brecciated Microcrystalline Quartz (SiO2)
sedimentary
Chert (Field Stone/Pebble)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Unakite
Epidotized Granite
metamorphic
Banded Agate (Botswana Agate)
Silicon Dioxide (SiO2)
mineral
Pumice
Pumice (Amorphous volcanic glass)
igneous
Quartzite
Quartzite (Primary mineral: SiO2)
metamorphic
Granite
Granite
Igneous
Red Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with Fe2O3 inclusions)
metamorphic
Epidote (or Epidote-rich rock)
Epidote. Mineral formula: Ca2(Al,Fe)3(SiO4)3(OH).
Mineral, often found in metamorphic rocks but also in sedimentary and igneous rocks
Slate with Quartz Vein
Foliated Metamorphic Rock (Mainly Quartz, Muscovite, Chlorite)
metamorphic
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Quartzite
Quartzite (SiO2)
metamorphic
Mahogany Obsidian
Volcanic Glass with Hematite or Magnetite inclusions (SiO2 + Fe2O3)
igneous
Quartzite River Stone
Quartzite (SiO2)
metamorphic
Pink Quartzite Pebble
Metamorphic Quartzite (SiO2 with iron oxide inclusions)
metamorphic
Quartzite
Quartzite (SiO2)
metamorphic
BROWN GRANITE (likely 'Tan Brown' or similar)
Granite (specifically a variety rich in orthoclase feldspar, often with biotite and possibly hornblende)
igneous
Citrine (Heat-treated Amethyst)
Silicon Dioxide (SiO2) with iron impurities
mineral
Pumice
Pumice (Vitreous pyroclastic rock)
igneous
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
Mineral
Limonite and Goethite on Gossan
FeO(OH)·nH2O
mineral
Granite Pebble
Granite (composed mainly of Quartz, Feldspar, and Mica)
igneous
Chert / Flint
Microcrystalline Quartz (SiO2)
sedimentary
Chert (often called Flint in dark varieties)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Rhodonite
Rhodonite (MnSiO3)
mineral
Banded Slate or Siltstone with Quartz/Calcite Veins
Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)
metamorphic
Green Aventurine
Quartz variety (SiO2 with inclusions)
mineral
Peridot and Citrine Gemstones (in a ring setting)
Peridot (Olivine: (Mg,Fe)2SiO4), Citrine (Quartz: SiO2)
mineral
Ferruginous Quartzite (Iron-stained Quartzite)
Quartzite with Iron oxides (FeO(OH) / Fe2O3)
metamorphic
Quartzite
Quartzite (SiO2)
metamorphic
Gneiss
Foliated Metamorphic Rock (Gneiss)
metamorphic
Quartzite Pebble
Recrystallized Quartz (SiO2)
metamorphic
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Specular Hematite (Specularite)
Iron Oxide (Fe2O3)
mineral
Quartzite
Quartzite (primarily SiO2)
metamorphic
Moonstone
Orthoclase (Potassium Aluminum Silicate), Formula: (K,Na)AlSi3O8
mineral
Rose Quartz
Silicon Dioxide with trace inclusions of dumortierite or titanium (SiO2)
mineral
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Mineral
Red Jasper
Jasper (Silicon Dioxide based crypto-crystalline Quartz with Iron inclusions)
sedimentary